The FN company is better known for its early four cylinder bikes but they also ran a successful single cylinder road racer program in the early 30s. The successor to that bike was this supercharged twin first raced in 1937. The engine was a long stroke design and the two cylinders were separate, to the point of having an individual overhead cam for each cylinder, each driven with its own cam chain and sprockets. The bike was fast but was fragile suffering from cast pistons which were not up to the high pressures afforded by the Rootes type supercharger. The coming of WW2 put an end to the the bikes career.